A Rare Case of Pituitary Apoplexy Associated with COVID Infection Presenting with Central Diabetes Insipidus

Pituitary apoplexy (PA) is rare and occurs in up to 20% of patients with a non-functioning pituitary adenoma. It can occur de novo or can be precipitated by surgery, head trauma, anticoagulant therapy, and pregnancy among others. Incidence of persistent Diabetes Insipidus (DI) is only about 2% in such patients. Limited literature exists on the association of PA and COVID infection. We present a case of PA and subsequent central DI in a patient with a pituitary adenoma and severe COVID-19 pneumonia.

Case Description:

A 64-year-old male with a history of a non-functioning pituitary macroadenoma (2 cm) of 5 months duration, primary hypothyroidism, and acute myeloid leukemia on chemotherapy presented to the emergency department with one day of headache, fever, and cough. He was diagnosed with COVID-19 pneumonia and started on dexamethasone, broad spectrum antibiotics and supplemental oxygen. Sudden loss of peripheral vision in his left eye with a persistent headache and altered mental status led to plain computed tomography that revealed a hyperattenuating suprasellar mass compressing the optic chiasm. MRI brain showed a T2 hypointense acutely hemorrhagic suprasellar mass compressing the infundibulum and the optic chiasm indicative of PA. Labs showed thrombocytopenia with platelet count 55,000/mcL (130-400), low AM cortisol 3 mcg/dL, normal prolactin 10 ng/mL, normal thyroid function and preserved somatotrophic axis. In addition, the patient developed polyuria with a urine output of up to 8 liters in a 24-hour period, acute hypernatremia (sodium 172 mmol/L), urine specific gravity < 1.005 and serum osmolality 360 mOsm/kg (275-295 mOsm/kg). Conservative management with stress dose hydrocortisone and desmopressin was the first line of therapy. Levothyroxine was continued at home dose. After resolution of COVID-19 pneumonia and improvement in electrolyte disarray, the patient underwent pituitary decompression surgery in 3 weeks with subsequent resolution of DI post-operatively. He was discharged home on hydrocortisone (20 mg total daily dose) and levothyroxine with close endocrinology follow up.

Discussion:

Association of COVID infection and PA has been reported in 10 patients in the literature so far. Although the exact mechanism is unknown, SARS-CoV-2 neural invasion via cerebral ACE-2 expression can lead to oxidative stress and thrombogenesis, ultimately predisposing to neural hemorrhage. Thrombocytopenia secondary to chemotherapy can be a contributing factor in our patient. DI is rare and usually resolves after decompression surgery. Further research focusing on the association and pathophysiology of COVID-19 with PA in those without precipitating factors are needed.